Alcohol use disorders impact millions of individuals and constitute one of the most serious public health problems worldwide. Despite its devastating impact on society, there are still few effective medications currently available. It is well-known that alcohol and nicotine are commonly abused together, and that ethanol and nicotine have direct affects on neuronal nicotinic acetylcholine receptors (nAChRs). These receptors have been shown to modulate the mesolimbic dopamine system and contribute to the reinforcing actions of both ethanol and nicotine. The nAChRs are pentameric ligand-gated ion channels and in the CNS there are at least twelve receptors, designated 12 to 110, and 22 to 24 that assemble into multiple combinations. My lab discovered that varenicline, a drug that primarily binds to 1422 nAChRs and approved by the FDA as a smoking cessation aid, reduces ethanol self-administration and heavy drinking following long-term ethanol exposure. We will determine the consequences of long-term ethanol exposure on the role and expression of 1422 nAChRs following voluntary heavy ethanol consumption, operant self-administration and in stress- induced reinstatement. We will integrate behavioral and biochemical techniques to identify the brain regions mediating the effects of long-term ethanol exposure on the expression of nAChRs. The long-term goal is to design better therapeutic agents that target nAChRs for the treatment of alcohol use disorders.